head lines on the kevin collins case. >> san francisco police are asking for the public's help in finding additional information about the man than a therrien, the man kron for firms identified as su4 disappearance of kevin collins. >> he has a history of kidnapping and sexual assault involving children. in 1981 he was arrested in the fisherman's wharf area for kidnapping a lonnd lewd acts are a child. he was bailed out, then was a no show at his court date. >> in 1982 he was arrested on that outstanding war, then pleaded guilty to felony lewd acts on a child. he was sentenced to six months in jail and three years' probation. >> therrien was also wanted in canada for a crime in 1973. >> police say he kidnapped and sexually assaulted two children. >> he was arrested and charged, but once he was released, he fled canada. >> police say he was never caught because, in part, used so many different names. >> san francisco police chief great suhr says the kevin collins case as long haunted him and his department. he says he remembers when collins went missing. he was relatively new on